Approach:
A two year study will investigate possible effects of rootworm Bt (Cry34/35Ab1) corn on carabid beetles. Corn hybrids will include Roundup Ready Cry34/35Ab1 corn, known as Herculex (R) RW [HR-RW], and a non-Bt near isoline [NBt-Iso]. Insecticides would include seed treatments Poncho 1250, Cruiser 250, and tefluthrin applied once at planting. The following treatments will be arranged in a RCB and replicated four times: 1) HR-RW (no insecticide); 2) NBt-Iso (check, no insecticide); 3) HR-RW with Poncho 1250; 4) NBt-Iso with Poncho 1250; 5) HR-RW with Cruiser 250 + tefluthrin; and 6) NBt-Iso with Cruiser 250 + tefluthrin. Pitfall traps will be used to sample beetles ten times over each growing season.